2,968 research outputs found
Gaze and Gestures in Telepresence: multimodality, embodiment, and roles of collaboration
This paper proposes a controlled experiment to further investigate the
usefulness of gaze awareness and gesture recognition in the support of
collaborative work at a distance. We propose to redesign experiments conducted
several years ago with more recent technology that would: a) enable to better
study of the integration of communication modalities, b) allow users to freely
move while collaborating at a distance and c) avoid asymmetries of
communication between collaborators.Comment: Position paper, International Workshop New Frontiers in Telepresence
2010, part of CSCW2010, Savannah, GA, USA, 7th of February, 2010.
http://research.microsoft.com/en-us/events/nft2010
New elevational record for Walker’s Slender Snake, Tachymenis attenuata Walker 1945 (Squamata: Dipsadidae), with notes on taxonomy and natural history
Predation by a Black Mussurana, Clelia clelia (Daudin 1803) (Serpentes: Dipsadidae), on an Andean Lancehead, Bothrocophias andianus (Amaral 1923), in Bolivia
Cosmic bulk viscosity through backreaction
We consider an effective viscous pressure as the result of a backreaction of
inhomogeneities within Buchert's formalism. The use of an effective metric with
a time-dependent curvature radius allows us to calculate the luminosity
distance of the backreaction model. This quantity is different from its
counterpart for a "conventional" spatially flat bulk viscous fluid universe.
Both expressions are tested against the SNIa data of the Union2.1 sample with
only marginally different results for the distance-redshift relation and in
accordance with the CDM model. Future observations are expected to be
able to discriminate among these models on the basis of indirect measurements
of the curvature evolution.Comment: 18 pages, 6 figures, comments and references added, accepted for
publication in GR
Challenges to the Effective Implementation of Competition Policy in Regulated Sectors: The Case of Telecommunications in Mexico Symposium on Competition Law and Policy in Developing Countries
This article reviews Mexico\u27s competition law and policy, with particular emphasis on the challenges that the Federal Competition Commission ( CFC ) has faced in implementing an effective competition policy. Some of the difficulties analyzed are the loopholes in the current laws, the lack of cooperation between the CFC and other sectoral regulators, and the regulatory arbitrage by market participants. These challenges are then illustrated by the developments in the telecommunications sector. This sector is particularly interesting in the case of Mexico given the overwhelming power of the dominant firm and the overlapping and even conflicting mandates of the different government authorities overseeing the sector. The article concludes with a series of specific policy recommendations aimed at improving the effectiveness with which the competition authority in Mexico implements competition policy
Exploring the effects of primordial non-Gaussianity at galactic scales
While large scale primordial non-Gaussianity is strongly constrained by
present-day data, there are no such constraints at Mpc scales. Here we
investigate the effect of significant small-scale primordial non-Gaussianity on
structure formation and the galaxy formation process with collisionless
simulations: specifically, we explore four different types of
non-Gaussianities. Generically, we find a distinct and potentially detectable
feature in the matter power spectrum around the non-linear scale. We then show
in particular that a negatively-skewed distribution of the potential random
field, hence positively skewed in terms of overdensities, with at these scales, implies that typical galaxy-sized halos reach
half of their present-day mass at an earlier stage and have a quieter merging
history than in the Gaussian case. Their environment between 1 and 5 virial
radii at is less dense than in the Gaussian case. This quieter history
and less dense environment has potentially interesting consequences in terms of
the formation of bulges and bars. Moreover, we show that subhalos have a more
flattened distribution around their host than in the Gaussian case, albeit not
as flattened as the 11 most massive Milky Way satellites, and that the two most
massive subhalos tend to display an interesting anti-correlation of velocities
around their host, indicative of kinematic coherence. All these hints will need
to be statistically confirmed in larger-box simulations with scale-dependent
non-Gaussian initial conditions, followed by hydrodynamical zoom-in simulations
to explore the detailed consequences of small-scale non-Gaussianities on galaxy
formation.Comment: 23 pages, 8 figures, 3 tables, comments welcome
Cognitive and personality variables as predictors of sexism against women in Spanish adolescents
Previous research on the antecedents of sexism against women have not considered simultaneously the effects of sex, personality, and cognitive variables (need for closure and critical thinking disposition) in relation to sexism. We evaluated whether in adolescence, these indicators could predict sexist attitudes towards women using structural models. The sample comprised 709 Spanish high-school students (mean age = 16.79). 51.5% were female. Sex (being male), need for closure and critical thinking were the most relevant predictors of sexism. The disposition to think critically is as relevant as the motivational dimension of cognition (need for closure) to predict sexism. Multi-group structural models by sex were estimated, and a moderator effect was found between openness to experience and sexism. We suggest future lines of research to disentangle the effects of personality and cognition on sexism and to guide intervention programs to reduce sexist attitudes among adolescents
Evolution of globular-cluster systems of ultra-diffuse galaxies due to dynamical friction in MOND gravity
Funding: MB and HSZ are thankful for the financial support by Cercle Gutenberg. MB acknowledges the support from the Polish National Science Centre under the grant 2017/26/D/ST9/00449. BF and RI acknowledge financial support from the European Research Council (ERC) under the European Unions Horizon 2020 research and innovation programme (grant agreement No. 834148). O.M. is grateful to the Swiss National Science Foundation for financial support.Context. Dynamical friction can be used to distinguish Newtonian gravity and modified Newtonian dynamics (MOND) because it works differently in these frameworks. This concept, however, has yet to be explored very much with MOND. Previous simulations showed weaker dynamical friction during major mergers for MOND than for Newtonian gravity with dark matter. Analytic arguments suggest the opposite for minor mergers. In this work, we verify the analytic predictions for MOND by high-resolution N-body simulations of globular clusters (GCs) moving in isolated ultra-diffuse galaxies (UDGs). Aims. We test the MOND analog of the Chandrasekhar formula for the dynamical friction proposed by Sánchez-Salcedo on a single GC. We also explore whether MOND allows GC systems of isolated UDGs to survive without sinking into nuclear star clusters. Methods. The simulations are run using the adaptive-mesh-refinement code Phantom of Ramses. The mass resolution is 20 M⊙ and the spatial resolution 50 pc. The GCs are modeled as point masses. Results. Simulations including a single GC reveal that, as long as the apocenter of the GC is over about 0.5 effective radii, the Sánchez-Salcedo formula works excellently, with an effective Coulomb logarithm increasing with orbital circularity. Once the GC reaches the central kiloparsec, its sinking virtually stops, likely because of the core stalling mechanism. In simulations with multiple GCs, many of them sink toward the center, but the core stalling effect seems to prevent them from forming a nuclear star cluster. The GC system ends up with a lower velocity dispersion than the stars of the galaxy. By scaling the simulations, we extend these results to most UDG parameters, as long as these UDGs are not external-field dominated. We verify analytically that approximating the GCs by point masses has little effect if the GCs have the usual properties, but for massive GCs such as those observed in the NGC 1052-DF2 galaxy, further simulations with resolved GCs are desirable.Publisher PDFPeer reviewe
Prevalence and clinical characteristics of phenobarbitone-associated adverse effects in epileptic cats
Objectives:
The study objective was to investigate the prevalence and clinical characteristics of phenobarbitone-associated adverse effects in epileptic cats.
Methods:
The medical records of two veterinary referral clinics from 2007 to 2017 were searched for cats fulfilling the inclusion criteria of a diagnosis of epilepsy, treatment with phenobarbitone and available follow-up information on the occurrence of adverse effects. Follow-up information was obtained from the medical records of the primary veterinarian and referral institutions and a questionnaire completed by the cats’ owners.
Results:
Seventy-seven cats met the inclusion criteria. Fifty-eight were affected by idiopathic epilepsy and 19 by structural epilepsy. One or more of the following adverse effects were reported in 47% of the cats: sedation (89%); ataxia (53%); polyphagia (22%); polydipsia (6%); polyuria (6%); and anorexia (6%). Logistic regression analyses revealed significant associations between adverse effect occurrence and both phenobarbitone starting dosage and administration of a second antiepileptic drug (AED). For each 1 mg/kg q12h increment of phenobarbitone, the likelihood of adverse effects increased 3.1 times. When a second AED was used, the likelihood of adverse effects increased 3.2 times. No association was identified between epilepsy aetiology and adverse effect occurrence. An idiosyncratic adverse effect, characterised by severe neutropenia and granulocytic hypoplasia, was diagnosed in one cat. This resolved following phenobarbitone discontinuation.
Conclusions and relevance:
The prevalence of phenobarbitone-associated adverse effects was 47%. Sedation and ataxia were most common. These are type A adverse effects and are predictable from phenobarbitone’s known pharmacological properties. In the majority of cases, adverse effects occurred within the first month of treatment and were transient. Idiosyncratic (type B) adverse effects, which were not anticipated given the known properties of the drug, occurred in one cat. Increased phenobarbitone starting dosage and the addition of a second AED were significantly associated with the occurrence of adverse effects
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